Simmer Docs

MCP

Connect Claude Code, Codex, Claude Desktop, and other MCP clients to read reporting and activity data from one Simmer project over OAuth.

Simmer provides a hosted Model Context Protocol (MCP) server for read-only access to your project data. Connect an MCP client and your assistant can query channels, conversion journeys, and visitor activity directly.

Endpoint

The hosted MCP server uses Streamable HTTP at:

https://app.letsimmer.com/mcp

Each connection authorizes a single project. To connect another project, add a separate connection.

Authentication

Connect with OAuth. Every supported client authorizes through an in-browser OAuth flow — you sign in to Simmer, choose the project to connect, and approve read-only access. There's no need to manually create an API key, copy a token, or paste a secret into a config file.

Under the hood, the OAuth grant is backed by an automatically managed, project-scoped key, so MCP access shares the same scopes, rate limits, revocation, and audit trail as the Public API. You manage and revoke connections from the project's API page.

The flow uses OAuth 2.1 with dynamic client registration and PKCE, so clients that support remote MCP servers connect without any pre-registered credentials.

Connect a client

Claude Code

Add the server

claude mcp add --transport http simmer https://app.letsimmer.com/mcp

Use --scope user to make the server available across all your projects, or --scope project to share it with your team via a checked-in .mcp.json. The default is local to the current project.

Authenticate

Run /mcp inside a Claude Code session and select simmer. Claude Code opens the browser OAuth flow — sign in, pick a project, and approve. Tokens are stored and refreshed automatically.

Codex

Add the server

codex mcp add simmer --url https://app.letsimmer.com/mcp

This writes an entry to ~/.codex/config.toml:

[mcp_servers.simmer]
url = "https://app.letsimmer.com/mcp"

If Codex doesn't connect to the remote server, enable the streamable HTTP client by adding:

[features]
experimental_use_rmcp_client = true

Authenticate

codex mcp login simmer

This launches the browser OAuth flow. Sign in, choose a project, and approve. Credentials are stored in your OS keyring.

Claude Desktop

Add a custom connector

Open Settings → Connectors → Add custom connector and enter the MCP server URL:

https://app.letsimmer.com/mcp

Leave the optional OAuth client ID and secret blank — the connection registers itself.

Authenticate

Claude Desktop opens the browser OAuth flow when you add the connector. Sign in to Simmer, choose the project to connect, and approve read-only access.

On Team and Enterprise plans, an organization owner adds the connector under organization settings first; members then enable it.

Other clients

Any MCP client that supports remote Streamable HTTP servers with OAuth (Cursor, VS Code, Windsurf, Zed, and others) connects the same way — point it at https://app.letsimmer.com/mcp and complete the browser authorization.

For header-capable clients that don't implement the OAuth flow, you can instead create a Public API key on the project's API page and configure the client to send it as a bearer token:

Authorization: Bearer YOUR_PUBLIC_API_KEY

Use OAuth where it's available — the bearer-token path is only a fallback for clients without OAuth support.

Tools

MCP tools are read-only and use the same response envelopes as the Public API. Tool discovery only shows tools allowed by the connection's scopes. get_channel_drilldown returns landing-page breakdowns in landing_page; source and medium describe the traffic source instead of carrying page paths.

ToolScope
get_overviewreporting:read
list_channelsreporting:read
get_channel_drilldownreporting:read
list_conversion_journeysreporting:read
get_conversion_journeyreporting:read
get_insightsreporting:read
list_insights_channelsreporting:read
list_unconverted_visitorsactivity:read
get_unconverted_visitoractivity:read

Date filters use the same from, to, and timezone fields as the Public API. Use YYYY-MM-DD dates.

Manage access

Open the project's API page to review connected MCP clients and their managed, MCP-backed keys.

Revoking an MCP connection disables that client immediately. Revoking the managed key for a connection also disables MCP access for that client.

FAQ

V1 limits

MCP access is hosted-only in v1. Self-hosted MCP servers, local stdio packages, Server-Sent Events transport, write tools, and MCP resources are not supported.

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